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Does Firefox support .mp4 video?

  • 3 replies
  • 1 has this problem
  • 383 views
  • Last reply by WoodyFF

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On page https://support.mozilla.org/en-US/kb/html5-audio-and-video-firefox?redirectslug=viewing-html5-audio-and-video&redirectlocale=en-US

I find "AAC and H.264/MPEG-4 AVC are patented audio/video compression formats. They can be viewed in Firefox using built-in OS libraries (so neither Mozilla nor you need to pay a fee) if embedded in the MP4 container format (.mp4, .m4a, .m4p, .m4b, .m4r, .m4v file types)."

But when I create an HTML page with the following HTML5 code:

<!DOCTYPE html>
<html>
<body>
</body>
This is a test of video.
<video src="C:/MyVideoFile.mp4" controls>
</video>
</html>

I get the error "No video with supported format and MIME type found". Does Firefox in fact support .mp4 video? If so, what changes do I need to make in the HTML?

On page https://support.mozilla.org/en-US/kb/html5-audio-and-video-firefox?redirectslug=viewing-html5-audio-and-video&redirectlocale=en-US I find "AAC and H.264/MPEG-4 AVC are patented audio/video compression formats. They can be viewed in Firefox using built-in OS libraries (so neither Mozilla nor you need to pay a fee) if embedded in the MP4 container format (.mp4, .m4a, .m4p, .m4b, .m4r, .m4v file types)." But when I create an HTML page with the following HTML5 code: <pre><nowiki><!DOCTYPE html> <html> <body> </body> This is a test of video. <video src="C:/MyVideoFile.mp4" controls> </video> </html></nowiki></pre> I get the error "No video with supported format and MIME type found". Does Firefox in fact support .mp4 video? If so, what changes do I need to make in the HTML?

Modified by cor-el

Chosen solution

After further experimentation, the error is due to the path in src. It should be either

<video src="file://C:/MyVideoFile.mp4" controls>

OR

<video src="MyVideoFile.mp4" controls>
if the .mp4 is in the same directory as the HTML file (other relative paths are possible)
Read this answer in context 👍 0

All Replies (3)

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EDIT: The sample HTML I included got rendered (and there is no such file as MyVideo.mp4). Here it is again, replacing angle brackets with square brackets for visibility: [!DOCTYPE html] [html] [body] /body This is a test of video. [video src="C:/MyVideoFile.mp4" controls] /video /html

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See if this helps: Separate Security Issue: Update your Flash Player or remove it using these links; Uninstall Flash Player | Windows {web link} Uninstall Flash Player | Mac {web link}

Note: Windows users should download the ActiveX for Internet Explorer. and the plugin for Plugin-based browsers (like Firefox).

Note: Windows 8 and Windows 10 have built-in flash players and Adobe will cause a conflict. Install the plugin only. Not the ActiveX.

Flash Player Version: 32.0.0.344

https://get.adobe.com/flashpl.183ayer/ Direct link scans current system and browser Note: Other software is offered in the download. <Windows Only>

https://get.adobe.com/flashplayer/otherversions/ Step 1: Select Operating System Step 2: Select A Version (Firefox, Win IE . . . .) Note: Other software is offered in the download. <Windows Only> +++++++++++++++++++++++++++++++++++ See if there are updates for your graphics drivers https://support.mozilla.org/en-US/kb/upgrade-graphics-drivers-use-hardware-acceleration

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Chosen Solution

After further experimentation, the error is due to the path in src. It should be either

<video src="file://C:/MyVideoFile.mp4" controls>

OR

<video src="MyVideoFile.mp4" controls>
if the .mp4 is in the same directory as the HTML file (other relative paths are possible)